It might be "fine", but you don't gain anything here while introducing both indirection and coupling. DRY is _not_ about data repetition. Data repetition is fine.

Alice and Bob having the same birthday is coincidental. And even if they are actually twins, you rather say that they are twins separately.

In your example you are just preserving keystrokes, but you don't say anything of value with 'pizza_base'. You haven't shown that 'pizza_base' is worth keeping track of or even mentioning.

A pepperoni_pizza with thick crust or extra cheese is still a pepperoni_pizza. A hawaiian_pizza's sauce being tomato doesn't relate to a pepperoni_pizza's sauce.

When coding data, just be explicit, verbose and keep it simple. Our text editors, IDEs and database APIs have affordances to change data in bulk. Those things are orders of magnitude easier if your data is simple, dumb and not complected.